Averrhoa carambola, also known as star fruit, is an unusual oval fruit with huge therapeutic potential. It has been used for centuries in Ayurvedic and traditional Chinese medicines to treat ailments like fever, cough, diarrhoea, chronic headache, digestive issues, and skin infections.
Star fruit is bright yellow or green and comes in sour and sweet varieties. The skin is edible, and the flesh is crunchy, firm, and incredibly juicy—consistent with grapes. Its flavour is described as a combination of apple, pear, grape, and citrus. When the fruit is cut in cross-section, it resembles a star, giving it the name of star fruit. The star fruit tree grows to 20–30 feet with lilac-coloured flowers.
Star fruit has been cultivated for centuries in Southeast Asia, originating in Sri Lanka around 300 B.C.E. It was discovered by Portuguese explorers to India in the 16th century, who then brought it to other parts of the world. Star fruit is believed to have spiritual meaning in many cultures, particularly as a symbol of enlightenment and peace. For example:
- In India, the five points of the star represent the five elements: water, fire, earth, air, and space.
- In China, the star shape symbolizes harmony and unity since it incorporates yin and yang symbols.
- In Thailand, it is believed to bring good luck and ward off evil because of its connection to the stars.
- In Buddhism, the five points of the star represent the Five Perfections: generosity, morality, patience, effort, and meditation.
Star fruit’s many nutritional and medicinal properties are due to its phytonutrients, such as vitamin C and flavonoids. Flavonoids act as free-radical scavengers, giving star fruit a high level of antioxidant activity and hypoglycemic, hypotensive, anti-cholesterol, anti-inflammatory, antitumor, and immune-boosting qualities.
Star fruit contains potassium, phosphorus, and vitamin C, which help regulate electrolytes essential in maintaining blood pressure, regular heartbeats, and a healthy blood flow. These compounds, along with flavonoids, clear excess cholesterol out of the body, thus lowering the risk of heart disease. Laboratory studies have shown that the antioxidant compounds in star fruit reduce cholesterol levels and the risk of fatty liver in mice.
Of all the flavonoids, apigenin is one of the most widely distributed in the plant kingdom. Star fruit has an abundance of apigenin, also called carambola flavone, found in its leaves. Apigenin can cross the blood-brain barrier to affect the central nervous system. It acts as an antidepressant and antianxiety agent and has been studied as a treatment for Alzheimer’s and Parkinson’s disease.
Studies have also shown apigenin to be a powerful antioxidant and therapeutic agent to overcome diseases like inflammation, autoimmune diseases, neuro-degenerative diseases, and several types of cancers. It exhibits a protective role against lung cancer and, along with quercetin, has significantly delayed tumour growth in melanoma cells and prevented liver cancer in mice.
The magnesium in star fruit helps activate the chemical Gamma-aminobutyric acid that helps induce sleep.
Because of its significant soluble dietary fibre, star fruit has been used to treat digestive issues such as indigestion, irritable bowel syndrome, and constipation.
Star fruit can help reduce wrinkles and skin discoloration, making it a great anti-aging food. Star fruit’s high vitamin C content and presence of antioxidants protect the skin against free radical damage. Studies show that vitamin C also plays a vital role in collagen synthesis, which maintains the skin’s elasticity and firmness. It has an antiseptic effect on the skin when applied topically as a paste. This is beneficial for treating wounds, inflammation, insect bites, and skin infections. Some beauty specialists recommend this for fading scars from acne.
The wide variety of vitamins and minerals, including magnesium, iron, zinc, calcium, and phosphorus in star fruit, help promote better bone health and may reduce the risk of osteoporosis.
Star fruit’s sugar and calorie content is low, while its fibre and vitamin C are high, rendering it safe for diabetics. Studies have confirmed that the apigenin in star fruit regulates hyperglycemia, thyroid dysfunction, and lipid peroxidation in diabetic animal models. Another study reported apigenin in star fruit leaves lowered blood glucose and stimulated glucose-induced insulin secretion in diabetic rats.
One star fruit has approximately 28 calories, 6 grams of carbs, 4 grams of sugar, 31 milligrams of vitamin C, and 2.5 grams of fibre. See this USDA link for complete nutrition.
Star fruit contains caramboxin and oxalic acid, both harmful to individuals suffering from kidney failure, kidney stones, or those under kidney dialysis treatment. Eating large quantities of star fruit can result in serious adverse health effects.
Tips for Eating Star Fruit:
- Ensure it is ripe with a yellow colour and only hints of green.
- Cut off the ends and slice it to get the unique star shape.
- Eat it as is, add it to salads, and use it as a garnish.
- Add to Asian or Indian stews and curries.
- Cook it with seafood or shellfish dishes.
- Make into pies, jam, jelly, or chutney.
- Juice it to drink.
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Watercress: The ‘Most Nutritious’ Vegetable, Lowers Chronic Disease Risks, Strengthens Bones, Improves Gut Health
With its peppery flavour and vibrant green colour, the watercress has long been cherished as far more than just another salad green. This unassuming vegetable contains an astonishing concentration of vital nutrients for which it has been praised since ancient times.
Modern science is now revealing the secrets behind this superfood—once known as a cure for scurvy (pdf) among sailors at sea—and how it can help fight disease, strengthen the body, and add years to your life.
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